Turbo-electric railway motor car



July 11, 1939. SCHMER 2,165,982

TURBO-ELECTRIC R AILWAY MOTORCAH Filed March 17, 1938 2 Sheets-Sheet l INVENTOR AHRL Sci/HER M 5. QM

ATTORNEY July 11, 1939. K. SCHMER TURBO-ELECTRIC RAILWAY MOTORCAR Filed March 17, 1938 2 Sheets-Sheet 2 gkZS CONDENSER Patented July 11, 1939 UNITED STATES TURBO-ELECTRIC RAILWAY MOTOR CAR Karl Schmer, Berlin-Mariendori', Germany, assignor to General Electric Company, a corporation of New York Application March 17, 1938, Serial No. 196,487 In Germany March 16, 1937 12 Claims.

A variety of suggestions for supplying the auxiliary devices of turbo-electric motor-cars, such as the boiler feed-pump, the smoke-gas fan, the circulation pump, the condenser fan, the air pump for the condenser, the compressor motor, and the like, with the requisite driving energy, and for regulating the devices concerned, has already been made, in most cases with the intention to employ as source for said energy a small live-steam turbine or an exhaust-steam turbine either regulated additionally in dependency of the .load or remaining without any regulation as this is effected automatically by the amount of .the exhaust-steam.

All those arrangements suffer, first of all, from the drawback that the complete power-plant with its appurtenances constitutes a complicated structure, and that furthermore, small auxiliary turbines operate uneconomically by reason of their large specific consumption of steam, and the regulation of the number of revolutions, or of the admission, is expensive and complicated, especially if it is to be effected from a remote place or automatically. Also housing these auxil-' iary turbines is, from spatial reasons, sometimes very difiicult, especially as regards the requisite tubes for the live steam and for the exhaust steam; all these disadvantages become the more apparent, the smaller the driving performance and the available space are.

The present invention obviates all drawbacks and disadvantages hitherto experienced with the known constructions; the new constructions are distinguished by a highly economical consumption of steam, the arrangement and combination of their parts permits a convenient survey, as well as a convenient supply of the energy; the auxiliary devices pertaining to the equipment oi! the plant can be easily regulated and it is possible to operate them from a remote place and to watch them by inexpensive means. Besides, housing the driving motors for the auxiliary devices presents now no difliculties at all.

I attain the objects in view by employing the steam-turbine, besides for driving the main current-generator, also for driving an auxiliary current-generator rigidly coupled with said main current-generator and running with a constant number of revolutions and a constant voltage, said auxiliary current-generator being used for supplying with current the electromotors driving the auxiliary devices, for instance the smoke-gas or flue-gas fan blower, the auxiliarycondensing devices, the pumps, the condenser, the fuel supply devices, and the like. This manner of driving the auxiliary devices presents in view of the facts that with turbo-electric railway motor-cars there is available on the one hand a comparatively great driving performance for the auxiliary machines and on the other hand a comparatively small driving performance for the driving axles the simplest solution of the various problems, in'that it is the most economical one as regards steam-technics, the cheapest one as regards machine technics, and the simplest one as regards service-technics. In order to demonstrate the proportion between the performance demand of the auxiliary machines and the driving performances for the driving axles I mention that with a performance of the driving turbines of about 700 kw. the performance demand of all auxiliary machines together amounts to about from to kw.

The invention is illustrated diagrammatically and by way of example in the accompanying drawings in which Figure 1 shows a turbo-elec tric power plant in connection with the appertaining wiring diagram, Figures 2, 3 and 4 and 5 show certain details of pressure responsive and manually operated control devices for the motor driving auxiliary devices, while Fig. 6 is a diagrammatic view showing the arrangement of the apparatus in a locomotive structure.

The power plant of the locomotive consists of only one steam-turbine I which drives a main current-generator 2 delivering continuous current, as well as of an auxiliary current-generator 3 delivering continuous current and being firmly connected with the shaft of said main currentgenerator. The steam-turbine receives the steam through an inlet pipe 4 and a steam regulating valve 5 which is subjected to the action of a centrifugal regulator 1 by the intermediary of a rod 6. Said regulator is rotated from the turbine shaft by the intermediary of a gearing 8.

The main current-generator is equipped with a weak counter compound coil 9 which may however, be dispensed with, if desired. Said generator supplies current to the main net ID in which a small resistance ll intended for regulating purposes is provided. Connected up to said netare motor groups [2 and [3, of which the first I-2 drives the driving axle of the locomotive, whereas the motors of the second group I3 act on the driving axles of one or more trail cars of the train. The motors of said groups are continuous-current shunt-motors permitting regulations of their numbers of revolution. Into the main net I0 is inserted, between the said two motor groups, a strong-current coupling l4 bymeans of which the motor group I3 can be disconnected from said net or be connected up tothe same. In the drawings (Fig. 1) is shown that another strong-current Eoupling it may be provided behind the motor group H.

The main current generator has a main excit ing coil l5 which is supplied with current from the auxiliary net l6 (fed in turn by the auxiliary current-generator 3) across the speed regulator l'l. The regulation of the driving performance and of the running speed is eifected by means of the known Ward-Leonard control.

The auxiliary current-generator is of such a size that its output suifices to drive all auxiliary devices pertaining to the equipment of the plant. Connected up to the auxiliary net it which is supplied with current from the auxiliary current-generator 3 across an excess current remotecontrol switch are the individual auxiliary de-' vices pertaining to the equipment of the plant. The auxiliary current-generator is so regulated that its voltage and therefore, also the voltage of the auxiliary net it remains constant independent of the load existing at the time being. For this purpose there is, for instance, the shunt exciting coil 59 of the auxiliary current-generator regulated across the field regulator 2t by means of a voltage regulator ill of any desired construc tion.

In the constructional form of the invention il lustrated in the drawings by way of example the following auxiliary devices are supplied with emrent from the net l6:

1. The main exciting coil 15 of the-main current-- generator 2 In the supply lead for the existing coil is is in serted a switch 23 which can be remote-com trolled by a switching-on and switching-oil device or coil 24% of any desired suitable construction. The switch 28 is closed when the turbine has attained its nominal number of revolutions and the car is ready for running.

2. The control device 25 The control device is supplied with current across a switch 3. The driving motor for the flue-gas fem or blower 28 The motor ll is a continuous-current shuntmotor with 'regulable number of revolutions, and the regulation may be eiiected wholly or partly in dependency of the load. This may be efiecteol in the most varied manners, for instance in dependency of the position of the inlet-valve, or of the position of the centrifugal governor, or of the steam-pressure, or of the current of the main current-generator, or of the product of the voltage of this current, or of the product of the strength and the voltage of the current i. e., of the delivered output of the main current-genera tor. The impulse-giving devices active at the time being act indirectly or directly on the field. regulator 29 of the motor 277, as will be more fully explained hereinafter in connection with the Fig. 2. In Fig. l is shown by way of example suitable means for regulating the number of revolutions in dependency of the load. These means are designed as follows:

The fan motor 2? has a shunt main exiting coil 30 supplied with current from the net it across the field regulator 29 which can be re-adjusted by a device 3 9. But it is also well possible to subject said device 3! to the action of 0116 01 seve areaesc of the above-mentioned regulating impulses. Fig. 5 shows the field' regulator 29 connected through a linkage 29a for operation by the centrifugal regulator I so as to vary the speed of the motor 27 in dependency of the load, i. e., inversely with the speed of the turbine.

The fan motor is, furthermore, equipped with additional exciting coils 32, 33, counteracting the coil 3. As appears from Fig. 1 the additional action of the field coil 32 on the number of revo lutions of the fan motor 21 takes place in dependency of the performance of the main current-generator up to the net lil so that the additional exciting current is proportional to the voltage of the current-generator 2. The additional exciting coil 33 is connected up to the binding posts of the regulating resistance 9 inserted in to the main net ii. The drop of voltage at the resistance II and, therefore, also the excitation of thecoil 33 are proportional to the current of the main current-generator 2.

With the above described device is obtained, in correspondence with the demand for air of the furnace and with consideration of the characteristic of the fan 28, a load-dependent regulation of the number of revolutions of the smokegas fan motor 27 in approximate correspondence with the following law:

sponcling selection of the saturation proportions of the motor or by a corresponding ununiform stepping of the field-regulator resistances.

The driving motor 34 for the com devising fan" 35 There is nothing to prevent the driving oi this motor with a constant number of revolutions without any regard to the load at the time being. This presents the advantage that in the case of small loads the vacuum. in the condenser is higher than if the load is large, but the provision must be made that the condenser pressure does not exceed a certain predetermined maximum value. When this maximum. value has been attained, the power plant must he stopped or the output of the main current-gen erator 2 must be reduced. This manner of operation presents the advantage that the fan mo tor 3G continues to run with its full performance also if the loads are small or if the plant runs idle. Anyhow, service conditions are imaginable in which it may be advantageous to regulate also the fan motor 34 load-dependent in such a manner that the number of revolutions decreases if the load is small and increases if the load is large. The performance demand or a fan decreases, or increases respectively, in correspcndence with the third power of the number of revolutions, in consequence whereof a compare tlvely small regulation range of about from 2% to 40% of the nominal number of revolutions of the motor M will sufilce for the additional regulation of the number of revolutions.

This additional regulation of the'number of (ill revolutions of the fan motor 34 can be effected vs in a manner similar to the regulation of the fan motor 21. The main exciting coil 35 is connected up to the auxiliary net 16 across the field regulator 36. The device 31 re-adjusting this regulator corresponds with the similarly constructed device 3| of the fan motor 21, and similarly as with the motor is also the motor 34 provided with an additional exciting coil 38, with the aid of which the number of revolutions of the motor is regulated and through which passes a current proportional to the regulation impulses employed at the time being. In comparison to the motor 21, however, another method must be used with the pressure dependent regulation of the motor 34. Whilst, namely, if the regulation of the motor 21 takes place in dependency of the boiler pressure or of the pressure of the live steam, the number of revolutions of this motor must become smaller if the pressure rises, and larger if the pressure falls, matters are the reverse if the regulating impulse does not originate from the pressure of the live, steam, but from. the condenser pressure in which case the number of revolutions of the motor 34 must rise with the rise of the condenser pressure and must fall with the fall of this pressure.

Both motors, 21 and 34, are connected up to the auxiliary net across switches 39 and 39' respectively. These switches are operated by coils or devices 40 and 4| respectively.

5. 'The electromotor 42 for the brake-air compressor 43 i This motor is likewise connected up to the auxiliary net I6 across a protective switch 62 having acontrol device 63.

6. The electromotor 44 for the boiler feed pump 45 The number of revolutions of this motor insoiar as the regulation is to take place automatically, is regulated in such a manner that the water level in the boiler is kept as constant as possible. This can be attained by connecting up the motor 44 to the auxiliary net 1'6 across the switch 46. This switch is controlled by the device 41. The shunt-field of the motor 44 is regulated by means of a field regulator 48. The motor 44 is so controlled that it is switched on and 011 in dependency of the level 01 the water in the boiler. This can be attained in a simple manner by providing at the level indicator 49 two contacts 50 which are bridged by the water itself, as soon as the level has risen to a certain height. When the control circuit of the switch 46 is closed, the motor will be switched oiT, but it will be switched on as soon as the water level has become so low that the contacts 50 are disconnected from one another. Above these contacts another pair of contacts is provided at the level indicator, these contacts serving for,

switching on an alarm device when they are conductively connected with one another by the water level having risen above the admissible maximum height.

In the control circuit of the switching device or coil 41 is, furthermore, provided a series-resistance 52.

It the regulating impulses assisting in the additional re-adjustment of the number of revolutions of the individual motors are not constituted by, or based on, electrical measuring agents, provision must be made to transform the regulating impulse employed at the time being into a continuous current proportional to them.

Two constructional forms of means suited for this purpose are shown by way of example in Figs. 2 and 3, designed for use in connection with a pressure regulator. In Fig. 2 the device is intended for regulation of the number of revolutions in dependency of the boiler pressure, so as to maintain a predetermined steam pressure supply for the turbine I, whereas Fig. 3 shows a modified design to be used if the regulation of the number of revolutions is to take place in dependency of the condenser pressure. In both examples particular means, likewise illustrated by way of example, are provided for attaining that the admissible maximum number of revolutions of the motors for the auxiliary devices is not surpassed.

The pressure gauge 64 consisting, for instance, of a yieldable box of undulated sheet-metalis subjected to internal pressure through the pipe 65. Corresponding to the height of the steam pressure the box 64 re-adjusts by the intermediary of a rod 66 a regulation-indicator co-opcrating with a voltage-divider consisting of a resistance contact path 68 provided with a lefthand sliding member 69 and a right-hand sliding member 10. Further appertaining members are a battery II and current limit resistances 12 and 13. a

The additional regulation current is drawn from the binding-posts 14, it is either conducted in the above described manner to a booster exciting coil of the auxiliary motors orto the readjusting device 3| or 31 of the field-regulators of these motors. If the boiler pressure is only low, the pointer 61 will be turned to the left so that the voltage drawn from the implement increases and in consequence thereof also the number of revolutions of the respective auxiliary motor increases correspondingly. If, however, the boiler pressure sinks below a predetermined height the pointer 61 gets onto the sliding member 69 of the contact path, in which case the regulating voltage at hand remains unvaried on its maximum value, that is to say, the auxiliary motor, for instance the fan motor 34 cannot surpass a certain definite maximum number of revolutions. By varying the position of the end-point l5 of the contact path 69 it is rendered possible to choose at liberty that maximum number of revolutions, or the pressure corresponding to that pressure. The maximum number of revolutions can be adjusted at will by changing the size of the series-resistance.

In the further example shown in Figure 3 which is intended for regulating the number of revolutions for the auxiliary motor in dependency of the condenser pressure, the pressure depending re-adjustment of the pointer 61 takes place in the reverse manner. Therefore, when the pressure rises, the pointer travels to the left and when the pressure falls the pointer travels to the right.

The limitation of the maximum number of revolutions of the auxiliary motors can be effected in known manner, for instance, in this way that ii a certain definite and at liberty adjustable number of revolutions is surpassed a centrifugal switch becomes active and short-circuits a part of the field series resistance'whereby a continuous amplification and a reduction of the number of revolutions is attained.

In the device shown in Fig. 4 is disclosed the manner in which the numbers of revolutions of the auxiliary motors can be varied also directly from the field regulator I! (Fig. 1). Connected up to the binding posts 16 is the field of the main current-generator 2. The field regulator i1 cooperates with a voltage divider Tl designed in a manner similar to the voltage divider shown in Fig. 2 and being supplied with current by a battery I8.

I claim:

1. A turbo-electric vehicle, comprising asteam turbine, electric motor driving means for said vehicle, a main current generator driven by said turbine, means for connecting said motor driving means to said main current generator, an auxiliary current generator connected to said turbine so as to be driven thereby, an auxiliary device on said vehicle, an auxiliary electric motor for driving said auxiliary device, means electrically connecting said auxiliary electric motors to said auxiliary generator, and means responsive to the voltage of said main generator for controlling the speed of said auxiliary motor.

2. A turbo-electric vehicle, comprising a steam turbine, electric motor driving means for said vehicle, the main current generator driven at a substantially constant speed by said turbine, means for connecting said motor driving means to said main current generator, an auxiliary current generator connected to said turbine so as to be driven thereby at a constant speed, a fluegas blower on said vehicle, an auxiliary electric motor for driving said blower, means electrically connecting said auxiliary electric motor to said auxiliary generator, and means responsive to the speed oi said turbine for regulating the speed of said auxiliary motor.

3. A turbo-electric vehicle, comprising a, steam turbine, electric motor driving means for said vehicle, a main current generator driven by said turbine, means for connecting said motor driving means to said main current generator, an auxiliary current generator connected to said turbine so as to be driven thereby, auxiliary devices on said vehicle, auxiliary electric motors for driving said auxiliary devices, means electrically con necting said auxiliary electric motors to said auxiliary generator, field excitation means for said main generator connected to be energized from said auxiliary generator, and means responsive to the pressure of the steam supplied to said turbine for regulating the speeds of said auxiliary motors.

i. A turbo-electric vehicle comprising a steam turbine, speed responsive regulating means driven by said turbine for regulating the supply of steam to said turbine so as to cause said turbine to operate at a substantially constant speed, electric motor driving means for driving said vehicle, a main generator driven by said turbine, means for connecting said motor driving means to said main generator, an auxiliary generator connected to be'driven by said turbine, a fluegas blower on said vehicle, an auxiliary motor for driving said blower, means connecting said aux iliary motor to said auxiliary generator and means actuated by said regulating means for controlling the speed of said auxiliary motor.

5. A turbo-electric vehicle comprising a steam turbine, speed responsive regulating means driven by said turbine for regulating the supply of steam to said turbine so as to cause said turbine to operate at a substantially constant speed, electric motor means for driving said vehicle, a main generator driven by said turbine, means for connecting said motor means to said main generator, an auxiliary generator connected to be driven by said turbine, a flue-gas blower on said vehicle, an' auxiliary motor for driving said blower, a condenser-fan on said vehicle, an auxiliary motor for driving said condenser fan, means connecting said auxiliary motors to said auxiliary generator and means actuated bysaid regulating means for controlling the speed of each of said auxiliary motors.

6. A turbo-electric vehicle, comprising a steam turbine, electric motor means for driving said vehicle, a main current generator driven by said turbine, means for connecting said motor means to said main current generator, an auxiliary current generator connected to said turbine so as to turbine.

7. A turbo-electric vehicle comprising a steam turbine, electric motor means for driving said vehicle, a main current generator driven by said turbine, means for connecting said motormeans to said main current generator, an auxiliary current generator connected to said turbine so as to be driven thereby, a flue-gas blower on said vehicle, an auxiliary electric motor for. driving said blower, means electrically connecting said auxiliary motor to said auxiliary generator and means responsive to the pressure of the steam supplied to said turbine for controlling the speed of said auxiliary motor so as to maintain said steam pressure at a predetermined value' 8. A turbo-electric vehicle comprising la steam turbine, electric motor means for drivingv said. vehicle, a main current generator driven by said turbine, means for connecting said motor means to said main current generator, an auxiliary cur rent, generator connected to said turbine'so as to be driven thereby, a flue-:gas blower on said vehicle, an auxiliary electric motor for driving said iary motor to said auxiliary generator and means responsive to the voltage oi. said main generator for controlling the speed of said auxiliary motor.

9. A turbo-electric vehicle comprising a steam turbine provided with a steam condenser, electric motors for driving said vehicle, a main current generator driven by said turbine, means for connecting said motor means to said main current generator, an auxiliary current generator connected to said turbine so as to be driven thereby, a blower for the condenser on said turbine, an auxiliary motor for driving said blower, means electrically connecting said auxiliary motor to said auxiliary generator and means responsive to the pressure in the condenser for controlling the speed of said auxiliary motor.

10. A turbo-electric vehicle comprising a steam turbine, a constant speed regulator for said turbine, electric motor means for driving said vehicle, a main current generator driven by said turbine, means for connecting said motor means to said main generator, an auxiliary generator connected to be driven by said turbine, a flue-gas blower on said vehicle, an auxiliary motor for driving said blower, a connection connecting said auxiliary motor to said auxiliary generator, 2.

main exciting field winding for said auxiliary motor connected to said auxiliary generator through a regulating resistance, a second field winding on said auxiliary motor connected to said main generator so as to b s-energized in response to the voltage of said main generator and plating means for said auxiliary motor respon- 'sive to the pressure of the steam suppliedto said v d 9,105,982 I a third field exciting winding on said auxiliary motor energized in response to-the current supplied by said main generator, said second and third field windings being connected to act in opposition to said main field winding.

11. A turbo-electric vehicle comprising a steam turbine, a constant speed regulator for said turbine, electric motor means for driving said vehicle, a main current generator driven by said turbine, means for connecting said'motor means to said main generator, an auxiliary generator connected to be driven by said turbine, a,fiue-gasblower on said vehicle, an auxiliarymotor for driving said blower, means connecting said auxiliary motor to said auxiliary generator, a regulating resistance, a main exciting field winding generator, a third field exciting winding on said auxiliary motor energized in response to the ourrent supplied by said main generator, said second and third field windings being connected to act in oppositionto said main field winding and means responsive to the pressure of the steam J supplied tosaid turbine for operating said regulating resistance so as to vary the speed of said blower and thereby maintain said steam presturbine provided with a boiler, electric motor trically. connecting said auxiliary motor to said auxiliary generator and means responsive to the water level in' the boiler for controlling the speed of said auxiliary motor so as to maintain a predetermined water level.

KARL SCHMER. 

